DE2853806A1 - SUPPORT UNIT FOR A DRIVER'S CAB ON COMMERCIAL VEHICLES - Google Patents

Description

Support unit for a driver's cab on commercial vehicles

Driver's cabs are usually cushioned compared to the vehicle chassis to increase comfort, to protect the driver from strong vibrations, such as those caused by the unsprung axles of tractors. be transmitted. As passive suspensions, such cushioning inevitably leads to cabin movements the chassis, which can be dampened, but nonetheless for the user of the driver's cab are noticeable and can impair driving safety.

The object of the invention is to create a support unit for driver's cabs that actively supports any

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tive movements between the chassis and cabin and in this way the cabin is essentially free of movement holds without rocking movements.

This object is achieved by the characterized features of claim 1. In this embodiment in the event of a relative movement between the driver's cab and the cylinder, emptying or loading takes place of the actuating cylinder, so that this depending on whether a vehicle drives through a pothole or over a Increase moves, is extended or shortened, so that the car is kept at the same height. For one optimal support of a cabin should be provided at least three such support units. The equal pressure circle would only have to be designed in such a way that it makes the necessary hydraulic delivery rates available at all times. Such a constant pressure circuit can be brought to the full charge level without difficulty through the hydraulic system of the utility vehicle being held. A constant pressure circuit has a better response than a direct current circuit, wherein the pressure accumulator assigned to a constant pressure circuit can be used for cabin support without difficulty required high specific power density guaranteed. If a towing vehicle has a constant pressure servo braking system or a constant pressure trailer braking system, the loading valve required for this system can be used also supply the constant pressure circuit of the support unit. With small pressure accumulators directly on the support unit

its response time can be optimized. 30th

It is particularly advantageous if the measures are taken according to claim 2, since this Way an automatic compensation for the static deflection when climbing into a cabin Relative movement between the cabin and the chassis is possible.

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. ° S53806

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In the following, the invention is illustrated more schematically Drawings explained in more detail using an exemplary embodiment.

Fig. 1 shows a tractor cab as the preferred one

Field of application of a support unit according to the invention in side view;

Fig. 2 shows schematically the structure of a support unit according to the invention.

The tractor indicated in FIG. 1 has a self-supporting driver's cab 1, which has support units according to the invention 2 is supported on the tractor chassis. Below the driver's seat 4 in the interior of the cabin is the Cabin floor 5 pulled up to the lower edge of the seat, so that a guide device 6 has space below it outside the cabin, which is designed in this way in the present case is that the cabin only moves around those in the interior of the cabin above the driver's seat 4 Center of gravity S can run.

To support the cabin 1, four support units 2 are preferably provided, two at the front End of the cabin on both sides of the bonnet 7 and two at the rear, which are supported on the rear wheel axle 8.

The support unit 2 according to the invention has a Support cylinder 10, which is supported via a spring element 11 on the floor 9 of the driver's cab 1 and via the piston rod 12 of its support piston 13 is supported on the chassis 3 of the tractor so that angular movements around the lower Support point 14, but no axial movement is possible. With the support cylinder 10, the housing 15 is a way

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ORlGiNAL INSPECTED

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valve 16 firmly connected, which receives a piston valve that can assume the three positions A, B and C. With the help of this piston valve 17, the supporting piston front side 18, which is connected to the Housing 15 is connected, connected to a constant pressure circuit 20 or a pressureless return tank 21 which is connected to the housing 15 via the return line 22. The equal pressure circuit contains a Pressure accumulator 23, which is supplied by a constant pressure pump 26 via the pressure line 24 and a check valve 25 will. The pressure accumulator 23 is connected to the valve housing 15 via an inlet line 27. That Directional control valve 16 works in such a way that it is in position B, the drain line 19 from the supply line 27 and the return line 22 blocks, in the position A the supply line 27 connects to the drain line 19 and the latter in position C with the return line 22 connects. The piston valve 17 is supported on a two-armed lever 30, the tilt point 31 of which is on the chassis and which is connected with its one lever arm 32 via a linkage 33 to the piston valve 17. Of the The other lever arm 34 is connected to the piston 36 of an actuating cylinder 37 via a joint 35. The cylinder Like the housing 15 of the directional control valve 16, this actuating cylinder 37 is connected to the support cylinder 10 to form a unit, the working space 39 of its piston 40 being connected to the drain line 19 via an adjustable throttle 41 is.

The support unit works in the following way: If the driver's cab 1 by climbing from an or loaded with several people, the spring element 11 is compressed and the piston valve 17 opposite its housing 15 from that shown in FIG Shifted to position C so that the drainage

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device 19 is connected to the return line 22 and the support cylinder 10 is shortened. At the same time, liquid also flows out of the working space via the throttle 41 39 of the piston 40 of the actuating cylinder 37, so that it moves under the pressure of the spring 42 downwards is and thereby lifts the piston valve 17 back into the starting position B via the lever 30, whereby the static deflection of the cabin is compensated and the directional control valve is back in its starting position is located. The throttle 41 is designed so that it does not have any dynamic loads occurring when driving Sufficient flow is allowed so that for the frequency range in which the dynamic loads occur Drive occur, the actuating cylinder is ineffective.

If the tractor drives over a bump in the ground and thereby the support cylinder 10 is compressed by the When the spring element 11 is raised against the driver's cab 1, the valve housing 15 moves relative to the piston slide 17 such that its working position C is reached. This relative movement between the piston valve 17 and its housing 15 is raised by the leverage of the lever 30, the lever arm 34 of which is also raised is supported, so that even with a small relative movement there is immediate response and the drainage line 19 is connected to the return line 22, so that the support cylinder 10 is partially emptied and thereby shortened to compensate for the unevenness of the ground.

If, on the other hand, the tractor drives through a pothole, the chassis is lowered in relation to the driver's cab 1, whereby the support unit is also pulled down via the piston rod 12 and thereby the piston slide 17 is moved into position A with respect to its housing.

This adjustment also takes place at the slightest hint of a relative movement between the driver's cab.

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1 bine and chassis, as this movement is amplified via the lever 30. In position A, the support cylinder is supplied with pressure fluid from the pressure accumulator 23 and thereby extended so far that the piston valve 17 is again

5 assumes its neutral position, i.e. position B.

The support unit responds extremely quickly and compensates for any relative movements, so that the driver's cab always remains at rest and 10 does not vibrate.

In principle, the piston valve 17 could also be attached directly to the driver's cab 1, with then the design is to be made in such a way that position B is reached when the deflection is usually more static.

Ö30025 / 0384

Claims (2)

TD \ £ patent attorneys: IEDTKE - DÜHLING - IVNNF. Dipl.-Ing. H. Tiedtke GO Dipl.-Chem. G. Buehling RUPE - Hellmann Dipi.-m _g . r. Dipl.-Ing. R group ο QCQQ (XC Dipl.-Ing.B. Pellmann * ~ Bavariaring 4, P.O. Box 20 2403 8000 Munich 2 Tel .: 0 89-5396 53 Telex: 5-24 845 tipat cable: Germaniapatent Munich B 9374 Claims 1Λ support unit for a driver's cab on utility vehicles, characterized by at least one support cylinder (10), which with its support piston (13) on the chassis (3) axially fixed and its cylinder (10) is elastically supported on the cabin (1) and its cylinder (10) is a Movement unit with an era directional control valve (16), the valve body (17) of which alternately forms the front side of the support piston (18) connects to the pressure side of a constant pressure circuit (20) or an unpressurized drain (21) and to the Cabin is attached. 2. Support unit according to claim 1, characterized in that the valve body (17) via one arm (32) of a zv / egg-armed lever (30) mounted on the cabin (1) can be actuated, the other arm (34) of which with the The actuating piston (40) of an actuating cylinder (37) is connected, the piston front side (39) of which via an adjustable throttle (41) is connected to the front side (18) of the support piston (13) and which in turn is connected to the support cylinder (10) forms a movement unit. i / ud Ö30025 / 0364 Deutsche Bank (Munich) Account 51/61070 Dresdner Bank (Munich) Account 3939 844 Postscheck (Munich) Account 670-43-804 ORIGINAL INSPECTED